Negotiations that led to the agreement began in 1968 after several long delays. As a result of the agreement, the International Monitoring Commission (ICC) was replaced by the International Monitoring Commission (ICCS) to comply with the agreement. The main negotiators of the agreement were Henry Kissinger, U.S. national security adviser, and Lé C Théc, a member of the North Vietnamese political bureau. Both men were awarded the Nobel Peace Prize in 1973 for their efforts, although he refused to accept it. This is the end of the formal declaration. During the years of negotiations, we insisted on peace with honour. In my speeches to the nation on January 25 and May 8 , I set out the goals we thought were essential to peace with honour. The ceasefire came into effect on 27 January 1973 at 2400 greenwich Mean Time. The United States and the Democratic Republic of Vietnam express the hope that this agreement will ensure a stable peace in Vietnam and contribute to the maintenance of lasting peace in Indochina and Southeast Asia. I remember the last time I spoke to him.
It was just the day after New Year`s Day. He then spoke of his concern for peace, for peace, and I was grateful to have once again expressed his support for my efforts for such peace. No one would have appreciated this peace more than he did. Nixon asked the eminent Asian-American politician Anna Chennault to be his “channel to Mr. Thieu”; Chennault agreed and regularly reported to John Mitchell that Thieu had no intention of attending a peace conference. On November 2, Chennault told the South Vietnamese ambassador: “I just heard from my boss in Albuquerque, who says his boss [Nixon] is going to win. And you`ll tell your boss [Thieu] to hold on for a while longer.  Johnson learned about the NSA and was furious that Nixon had “blood on his hands” and that Senate Minority Leader Everett Dirksen agreed with Johnson that such an action was a “betrayal.”    Defence Minister Clark Clifford considered this to be an unlawful violation of the Logan Act.  In response, President Johnson ordered the listening of members of the Nixon campaign.
  Dallek wrote that Nixon`s efforts “probably made no difference” because Thieu was unwilling to participate in the talks and there was little chance of reaching an agreement before the elections; However, his use of the information provided by Harlow and Kissinger was morally questionable and Vice President Hubert Humphrey`s decision not to make Nixon`s actions public is “an unusual act of political decency.”  The provisions of the agreement were immediately and often violated by North and South Vietnamese forces without an official U.S. response. The North Vietnamese have accused the United States of carrying out bombings in northern Vietnam during this period. In March 1973, open fighting broke out and North Vietnamese crimes extended their control until the end of the year. Two years later, a massive North Vietnamese offensive seized South Vietnam on April 30, 1975, after which the two countries separated since 1954 met on July 2, 1976 as Vietnam.  North Vietnam insisted for three years that the agreement could not be reached unless the United States agreed to remove South Vietnamese President Nguyen Vén Thiu from power and replace him with someone more acceptable to Hanoi. Nixon and Kissinger were not prepared to sign an agreement to overthrow a government that had not overthrew the NLF by force of arms, although the scale of North Vietnam`s claims is controversial.